Patient movement and incontinence notification devices

ABSTRACT

A notification device is provided that includes a sensor pad, and an electronics module generates one or more notifications in response to signals received from the sensor pad. In a first embodiment, the sensor pad includes a pressure sensor for sensing pressure applied by a patient and generating a pressure signal, and conductive tracings for sensing moisture due to incontinence and generating a moisture detection signal when moisture is detected. In another embodiment, an absorbent sensor pad includes a sensor pad for sensing moisture and includes an absorbent chuck having a moisture-impermeable sheet with an absorbent material on an upper surface thereof, wherein the moisture-impermeable sheet has an aperture for receiving the sensor pad. The absorbent sensor pad may be provided in the form of a diaper.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application No.62/296,201 filed Feb. 17, 2016, entitled “PATIENT MOVEMENT ANDINCONTINANCE NOTIFICATION DEVICES,” the entire disclosure of which ishereby incorporated by reference herein.

BACKGROUND OF THE INVENTION

The present invention generally relates to a patient movementnotification device, an incontinence notification device, a diaper withan incontinence notification device, a combined patient movement andincontinence notification device, a combined chuck and incontinencenotification device, and a combined chuck, incontinence notificationdevice, and patient movement notification device.

Patient movement notification devices serve to notify a patient'scaretaker(s) who may better assist them. Such devices are used forpatients who are at a high risk for fall-related injury or for patientswho are not healthy enough to stand (post-operative patients, etc.).

Patient movement notification devices are currently in use that includea disposable sensor that is positioned between the patient and a bed,chair, or toilet, and an electronics module that connects to the sensorfor generating an alarm when the patient removes pressure from the padby getting out of bed or up from a chair. The alarm may be a recordedvocal command, such as “please stay in bed and use the nurse call buttonif you need assistance” or any other message that the caretaker may wishto record.

Existing patient movement notification devices suffer from severaldrawbacks. First, they may tend to give false alarms when the patientmerely rolls over in bed. Second, they may not operate accurately whenused on an air mattress, particularly for patients weighing betweenabout 70 and 150 pounds because the sensor pads do not effectivelydiscriminate between a loss of pressure from above or below the sensorpad. The sensors are considered to be disposable and are typically onlyto be used for 15 days or less because the sensors are pressuresensitive, and after having pressure continuously applied to the sensor,the sensor may not be able to re-expand when the patient removespressure. However, hospitals have difficulty monitoring the times of usesuch that the sensors are often used well beyond the permitted 15-daylifetime.

Incontinence notification devices are known that are intended to detectwhen a patient has urinated in their bed. Such incontinence devices areplaced under the patient's groin area and trigger an alarm upon sensingmoisture, often by using conductive traces provided on the upper surfaceof a moisture-impermeable strip. The moisture-impermeable strips of suchincontinence notification devices are disposable and do not serve toabsorb urine.

Incontinence issues are often alternatively dealt with by using a“chuck,” which is a large disposable absorbent pad placed under thepatient. Such chucks are made of absorbent materials similar to thoseused in diapers. An example of such a chuck is disclosed in U.S. Pat.No. 6,675,702. Such chucks do not serve to notify a caregiver when apatient has urinated.

SUMMARY OF THE INVENTION

According to an embodiment of the present invention, a patient movementnotification device is provided comprising: a sensor pad comprising afirst sensing zone and a second sensing zone, the first sensing zonesenses pressure applied by the patient to the first sensing zone andgenerates a first pressure signal upon a sensing pressure applied by thepatient to the first sensing zone, the second sensing zone sensespressure applied by the patient to the second sensing zone and generatesa second pressure signal upon a sensing pressure applied by the patientto the second sensing zone; and an electronics module communicativelycoupled to the sensor pad for generating a notification of patientmovement in response to receipt or non-receipt of at least one of thefirst pressure signal and second pressure signal from the sensor pad.

According to another embodiment of the present invention, a sensor padis provided for use in a patient movement notification device. Thesensor pad comprises: a first sensing zone and a second sensing zone,the first sensing zone senses pressure applied by the patient to thefirst sensing zone and generates a first pressure signal upon a sensingpressure applied by the patient to the first sensing zone, the secondsensing zone senses pressure applied by the patient to the secondsensing zone and generates a second pressure signal upon a sensingpressure applied by the patient to the second sensing zone.

According to another embodiment of the present invention, a notificationdevice is provided for providing both patient movement notification andincontinence notification. The notification device comprises: a sensorpad comprising a pressure sensor for sensing pressure applied by apatient and generating a pressure signal upon a sensing pressure appliedby the patient, the sensor pad further comprises first and secondcontiguous conductive tracings provided on an upper outer surfacethereof for sensing moisture due to incontinence and generating amoisture detection signal when moisture spans the first and secondconductive tracings; and an electronics module communicatively coupledto the sensor pad for generating a notification of patient movement inresponse to receipt of the pressure signal from the sensor pad, and forgenerating a notification of incontinence in response to receipt of themoisture detection signal from the sensor pad.

According to another embodiment of the present invention, a sensor padis provided for providing both patient movement notification andincontinence notification. The sensor pad comprises: a pressure sensorfor sensing pressure applied by a patient and generating a pressuresignal upon a sensing pressure applied by the patient, the sensor padfurther comprises first and second contiguous conductive tracingsprovided on an upper outer surface thereof for sensing moisture due toincontinence and generating a moisture detection signal when moisturespans the first and second conductive tracings.

According to another embodiment of the present invention, anincontinence notification device is provided comprising: a sensor padcomprising first and second contiguous conductive tracings provided onan upper outer surface thereof for sensing moisture due to incontinenceand generating a moisture detection signal when moisture spans the firstand second conductive tracings; an absorbent chuck comprising amoisture-impermeable sheet with an absorbent material on an uppersurface thereof, wherein the moisture-impermeable sheet of the chuck hasan aperture for receiving the sensor pad such that the first and secondconductive tracings on the sensor pad are exposed through or above theaperture; and an electronics module communicatively coupled to thesensor pad for generating a notification of incontinence in response toreceipt of the moisture detection signal from the sensor pad.

According to another embodiment of the present invention, an absorbentsensing pad is provided for use with an incontinence notificationdevice. The absorbent sensing pad comprises: a sensor pad comprisingfirst and second contiguous conductive tracings provided on an upperouter surface thereof for sensing moisture due to incontinence andgenerating a moisture detection signal when moisture spans the first andsecond conductive tracings; and an absorbent chuck comprising amoisture-impermeable sheet with an absorbent material on an uppersurface thereof, wherein the moisture-impermeable sheet of the chuck hasan aperture for receiving the sensor pad such that the first and secondconductive tracings on the sensor pad are exposed through or above theaperture.

According to another embodiment of the present invention, a notificationdevice is provided for providing both patient movement notification andincontinence notification. The notification device comprises: a sensorpad comprising a pressure sensor for sensing pressure applied by apatient and generating a pressure signal upon a sensing pressure appliedby the patient, the sensor pad further comprising first and secondcontiguous conductive tracings provided on an upper outer surfacethereof for sensing moisture due to incontinence and generating amoisture detection signal when moisture spans the first and secondconductive tracings; an absorbent chuck comprising amoisture-impermeable sheet with an absorbent material on an uppersurface thereof, wherein the moisture-impermeable sheet of the chuck hasan aperture for receiving the sensor pad such that the first and secondconductive tracings on the sensor pad are exposed through or above theaperture; and an electronics module communicatively coupled to thesensor pad for generating a notification of patient movement in responseto receipt of the pressure signal from the sensor pad, and forgenerating a notification of incontinence in response to receipt of themoisture detection signal from the sensor pad.

According to another embodiment of the present invention, an absorbentsensor pad is provided for use in a notification device for providingboth patient movement notification and incontinence notification. Theabsorbent sensor pad comprises: a sensor pad comprising a pressuresensor for sensing pressure applied by a patient and generating apressure signal upon a sensing pressure applied by the patient, thesensor pad further comprising first and second contiguous conductivetracings provided on an upper outer surface thereof for sensing moisturedue to incontinence and generating a moisture detection signal whenmoisture spans the first and second conductive tracings; and anabsorbent chuck comprising a moisture-impermeable sheet with anabsorbent material on an upper surface thereof, wherein themoisture-impermeable sheet of the chuck has an aperture for receivingthe sensor pad such that the first and second conductive tracings on thesensor pad are exposed through or above the aperture.

According to another embodiment of the present invention, a sensor padis provided for use in a patient movement notification device. Thesensor pad comprises: a central region; a first depending leg extendingfrom the central region in a first direction; a second depending legextending from the central region in a second direction, which isopposite the first direction; a third depending leg extending from thecentral region in a third direction, which is substantiallyperpendicular to the first and second directions; a fourth depending legextending from the central region in a fourth direction, which isopposite the third direction and substantially perpendicular to thefirst and second directions; and a pressure sensor for sensing pressureapplied by a patient and generating a pressure signal upon a sensingpressure applied by the patient.

According to another embodiment of the present invention, a diaper isprovided comprising: a sensor pad comprising first and second contiguousconductive tracings provided on an upper outer surface thereof forsensing moisture due to incontinence and generating a moisture detectionsignal when moisture spans the first and second conductive tracings; anda moisture-impermeable sheet with an absorbent material on an uppersurface thereof, wherein the moisture-impermeable sheet has an aperturefor receiving the sensor pad such that the first and second conductivetracings on the sensor pad are exposed through or above the aperture.

According to another embodiment of the present invention, a notificationdevice is provided for providing patient movement notification andincontinence notification. The device comprises: a mattress having anintegrated pressure sensor for sensing pressure applied by a patient andgenerating a pressure signal upon a sensing pressure applied by thepatient; a sensor pad comprising first and second contiguous conductivetracings provided on an upper outer surface thereof for sensing moisturedue to incontinence and generating a moisture detection signal whenmoisture spans the first and second conductive tracings; and anelectronics module communicatively coupled to the pressure sensor forgenerating a notification of patient movement in response to receipt ofthe pressure signal from the pressure sensor, the electronics modulecommunicatively coupled to the sensor pad for generating a notificationof incontinence in response to receipt of the moisture detection signalfrom the sensor pad.

These and other features, advantages, and objects of the presentinvention will be further understood and appreciated by those skilled inthe art by reference to the following specification, claims, andappended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a partial isometric view of a patient movement notificationdevice according to an embodiment of the present invention;

FIG. 1A is an elevational view of a cross section of a portion of theelectronics module of the patient movement notification device shown inFIG. 1 taken along line A-A;

FIG. 2 is an electrical circuit diagram in block form of the electronicsmodule of the patient movement notification device shown in FIG. 1;

FIG. 3 is a top plan view of a sensor pad according to a firstembodiment;

FIG. 4 is a cross-sectional view of a first version of an absorbentsensor pad according to a second embodiment;

FIG. 5 is a cross-sectional view of a second version of an absorbentsensor pad according to a second embodiment;

FIG. 6 is a top plan view of a sensor pad according to a thirdembodiment;

FIG. 7 is top plan view of a sensor pad according to a fourthembodiment;

FIG. 8 is a perspective view of a sensor pad of the patient movementnotification device shown in FIG. 1 shown in a partially assembledstate;

FIG. 9A is a perspective view of diaper having an incontinence sensingdevice;

FIG. 9B is an exploded perspective view of a diaper having anincontinence sensing device; and

FIG. 10 is a perspective view of an absorbent chuck/incontinence sensingdevice and a bed with which the patient movement notification device maybe integrated.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference will now be made in detail to the present preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numeralswill be used throughout the drawings to refer to the same or like parts.In the drawings, the depicted structural elements are not to scale andcertain components are enlarged relative to the other components forpurposes of emphasis and understanding.

Various embodiments of a notification device are described herein. Insome embodiments, the notification device issues a notification upondetection of patient movement. In other embodiments, the notificationdevice issues a notification upon detection of patient incontinence. Instill other embodiments, the notification device issues notificationsupon detection of patient movement and/or patient incontinence. In eachembodiment, the notification device 10 includes a sensor pad 100 and anelectronics module 15. The configurations of the sensor pad 100 andelectronics module 15 may vary from embodiment to embodiment.

The electronics module 15 may be configured as shown in FIG. 1 toinclude a housing 20 that contains the electronics (described below) andat least one battery 50 (FIGS. 1A and 2). The electronics that may beincluded in housing 20 are shown in FIG. 2. As shown, the electronicsmodule 15 includes a connector 79 that may be a connector receptacle toreceive a plug end of a wire extending from a sensor pad 100 or may be apermanent connection to the sensor pad. The electronics may take anyform capable of storing a voice recording and playing the voicerecording back upon determining that the patient is moving in responseto a signal from the sensor pad 100. As such, the electronics include amicrophone 60, a speaker 65, a RESET push button 67A, a HOLD push button67B, a controller 70 (which may be a microprocessor, digital signalprocessor, or discrete electronic components), memory 75 (which may bememory internal to a microprocessor), a voice recorder 76, an audioamplifier 77, connector 79 for connecting to the sensor pad 100, and oneor more batteries 50. In lieu of connector 79, the sensor pad 100 may behardwired to electronics module 15, particularly if the electronicsmodule is disposable so as to be disposed of with the sensor pad. Theelectronics may further include LED indicators 78 a and 78 b (FIG. 1),and a transmitter/receiver 80 as further described below.

Optional transmitter 80 may be provided to transmit information (whichmay include alarms and other data) to a distant receiver that receivesthe information. This information may then be stored in an automatedrecords database of the healthcare facility or otherwise at a nurses'station. The information may include any one or more of the following:warnings that a patient has wet their bed; warnings of a patient gettingout of bed, out of a chair or wheelchair, or off of a toilet; the timeand date of issuance of the warnings and the time and date the patientreturned to bed or the chair; warnings of sensor pad end of lifeapproaching with a time and date stamp; and warning of sensor pad end oflife with a time and date stamp. The time and date stamps may begenerated at the receiving side of the information and stored in therecords database. Transmitter 80 may be coupled wirelessly or by a wiredconnection such as a USB. The records database may be a database such asa Cerner or EPIC records database.

Transmitter 80 may be coupled wirelessly or by wired connection to anursing station alarm switchboard so as to generate appropriate alarmsignals at a nursing station that identify the patient or room and thewarnings so that the staff can take appropriate action. A connectionport 82 may be provided for a wired connection to the nursing station.

Controller 70 may also store historical information in memory 75 (orotherwise transmit the necessary information to the nursing stationand/or records database so that the historical information may bestored). Such historical information may include times of day that thepatient historically suffers from incontinence and/or gets out of bed orattempts to get out of bed. By tracking this historical information,nurses may be sent a warning via cell phone text or other alarmmechanism to check on the patient just prior to those historical timesso as to avoid the incontinence event altogether.

In some facilities, video monitoring may be used to identify when apatient has or is about to get out of bed. While this technique can beeffective, there are often too many monitors for one person to watch. Byusing the alarm system of the present invention, a nurse or other personwatching the video monitors may be warned to view a particular patient,when, for example, the fall prevention alarm is triggered. If thepatient has or is attempting to get out of bed, a nurse may be sent tothat room. However, if the patient has merely moved in bed so as totrigger the fall prevention alarm, the person watching the monitors maysee that a nurse does not need to respond and simply reset the alarmremotely. This cuts down on false notifications that would otherwiseconsume significant time of the nursing staff.

According to a first embodiment, notification device 10 is configuredfor providing patient movement notification and incontinencenotification. Accordingly, notification device 10 includes a sensor pad100 having a pressure sensor 111 (FIGS. 3 and 8) for sensing pressureapplied by a patient and generating a pressure signal upon a sensingpressure applied by the patient, also having a first contiguousconductive tracing 122 and a second contiguous conductive tracing 124provided on an upper outer surface 120 thereof for sensing moisture dueto incontinence and generating a moisture detection signal when moisturespans first and second conductive tracings 122 and 124. In this firstembodiment, electronics module 15 is communicatively coupled to sensorpad 100 for generating a notification of patient movement in response toreceipt of the pressure signal from sensor pad 100, and for generating anotification of incontinence in response to receipt of the moisturedetection signal from sensor pad 100. By providing both patient movementnotification and incontinence notification with the same notificationdevice 10, only one sensor pad 100 and one electronics module 15 need beprovided to perform both notification functions that previously requiredtwo separate sensor pads and two separate electronics modules.

Sensor pad 100 may be constructed as shown in FIGS. 1 and 3. In general,sensor pad 100 may be constructed in any manner so as to provide apressure sensor that senses pressure applied by a patient and generatesa pressure signal upon a sensing pressure applied by the patient.Specific constructions of this aspect of the sensor pad 100 aredescribed further below. In order to have sensor pad 100 function as anincontinence sensor, first contiguous conductive tracing 122 and secondcontiguous conductive tracing 124 are disposed on an upper surface 120of sensor pad 100. Each of the first and second contiguous conductivetracings may be printed on the surface of sensor pad 100 using anelectrically conductive ink in a pattern that maintains spacing betweenrespective interdigitated branches 126 and 128 of first and secondcontiguous conductive tracings 122 and 124. A wire 130 connects firstcontiguous conductive tracing 122 to controller 70 of electronics module15, and another wire 132 connects second contiguous conductive tracing124 to either controller 70 or a fixed voltage reference. Theinterdigitated branches 126 and 128 of first and second contiguousconductive tracings 122 and 124 are spaced far enough apart thatcontroller 70 detects an open circuit when sensor pad 100 is dry.However, when urine is present on upper surface 120 of sensor pad 100,the urine spans across the interdigitated branches 126 and 128 of firstand second contiguous conductive tracings 122 and 124 and therebycreates a path of electrical conductivity between first and secondcontiguous conductive tracings 122 and 124 such that controller 70senses a closed circuit. Upon sensing such a closed circuit, controller70 may generate an alarm and/or call to the nurses' station, which maybe sent via the existing nurse call system in the hospital. Electronicsmodule 15 may be configured such that the incontinence alarm or callwould continue until the sensor pad 100 is replaced with a new drysensor pad.

As used herein, the term “communicatively coupled” means that twocomponents are associated and configured so that they communicate withone another. Such communicative coupling may be provided by hardwiringthe devices or by providing for wireless communication therebetween.Thus, the sensor pad 100 may further include a transmitter and/or areceiver for sending/receiving wireless signals to/from electronicsmodule 15.

In accordance with a second embodiment, a notification device 10 asdescribed above in the first embodiment is used in combination with anabsorbent chuck 150 as shown in FIGS. 4 and 5. Absorbent chuck 150includes a moisture-impermeable sheet 152 (such as a plastic sheet) withan absorbent material 154 on an upper surface thereof.Moisture-impermeable sheet 152 of absorbent chuck 150 has an aperture155 for receiving sensor pad 100 such that first and second conductivetracings 122 and 124 on sensor pad 100 are exposed through or aboveaperture 155. Absorbent material 154 may extend over upper surface 120of sensor pad 100 (FIG. 5) or may be removed from that region abovesensor pad 100 (FIG. 4). By providing absorbent chuck 150 on/aroundsensor pad 100, urine may be absorbed by chuck 150 in a conventionalmanner to keep the bedding dry. Previously, the use of an absorbentchuck would make it difficult to use an incontinence sensor pad due tothe presence of the moisture-impermeable sheet 152 which would otherwiseblock the urine from reaching the sensor pad. Aside from being modifiedto include aperture 155 to accommodate sensor pad 100, absorbent chuck150 may be constructed in any conventional manner.

Although this embodiment is described as using the sensor pad 100 of thefirst embodiment, it should be appreciated that sensor pads according tothe other embodiments described herein may be used with absorbent chuck150. Further, a sensor pad may be used with the absorbent chuck thatonly senses incontinence and that does not also sense patient movement.

FIG. 6 shows an example of a third embodiment of a notification device10. In this third embodiment, sensor pad 100 is configured to include afirst sensing zone 200 and a second sensing zone 202 a. First sensingzone 200 senses pressure applied by the patient to the first sensingzone and generates a first signal upon a sensing pressure applied by thepatient to the first sensing zone 200. Second sensing zone 202 a sensespressure applied by the patient to the second sensing zone 202 a andgenerates a second signal upon a sensing pressure applied by the patientto the second sensing zone 202 a. Electronics module 15 generates anotification of patient movement in response to receipt or non-receiptof at least one of the first signal and second signal from sensor pad100 in the manner described below. As described below, a third sensingzone 202 b may optionally be provided that senses pressure applied bythe patient to the third sensing zone 202 b. Additional sensing zonesmay also be provided.

As discussed above, existing patient movement notification devices maytend to give false alarms when the patient merely rolls over in bed. Byproviding at least the two separate sensing zones 200 and 200 a, amulti-zone sensor pad 100 may be provided that more accuratelydetermines when a patient has moved off the bed or is about to move offthe bed while significantly reducing false alarms. This is accomplishedby providing a multi-zone sensing pad 100 that provides additionalinformation to electronics module 15 such that controller 70 may make amore accurate determination as to patient movement. The manner in whichcontroller 70 uses the information from the various zones is describedfurther below.

First sensing zone 200 is located on sensor pad 100 such that it will bedisposed at the center of the bed where the patient is most likely tolie. Second sensing zone 202 a is located on sensor pad 100 towards aside of the bed where the patient may exit the bed. If the optionalthird sensor zone 202 b is provided, third sensing zone 202 b is locatedon sensor pad 100 on an end of the sensor pad opposite an end wheresecond sensing zone 202 a is located so as to be positioned toward anopposite side of the bed where the patient may exit the bed. As will beapparent, a sensor pad 100 with a third sensing zone 202 b would mostlikely be used when a patent's bed is positioned to allow the patient toexit either side of the bed. If the bed is against a wall so that thereis only one side from which the patient may exit the bed, a two-zonesensor pad would be sufficient.

When used with a multi-zone sensing pad 100, electronics module 15 maybe configured to enter a monitoring mode upon receipt of the firstsignal generated from centrally located first sensing zone 200. Thus,receipt of the first signal indicates that the patient is applyingpressure to first sensing zone 200 and that the patient is now in bed.When in the monitoring mode, electronics module 15 does not generate anotification of patient movement so long as the first signal isreceived. Note that the first signal need not be continuously receivedas controller 70 may sample the output from sensor pad 100 at periodicintervals to conserve battery power. When in the monitoring mode,electronics module 15 generates a notification of patient movement wheneither (1) the first signal has not been received for a predeterminedtime period (of, for example, two seconds) and no signal is receivedfrom second sensing zone 202 a (or third sensing zone 202 b if present),or (2) the first signal is no longer being received but the secondsignal (or third signal if sensor pad 100 has a third sensing zone) isreceived thereby indicating that the patient has moved from firstsensing zone 200 to second sensing zone 202 a (or the optional thirdsensing zone 202 b) and is in the process of exiting the bed. By waitingfor the predetermined time period in the event that the first signal hasnot been received but no signal has been received from either the secondor third sensing zones, false alarms are prevented in the event thepatient has simply lifted up off the first sensing zone 200 whilerolling over. However, if the predetermined time period passes,electronics module 15 generates a notification of patient movementbecause it becomes likely that the patient has attempted to exit the bedfrom an end of the bed rather than a side of the bed as would haveotherwise been detected by the second or third sensor zones 202 a and202 b.

The notification of patient movement generated by electronics module 15may include an audio and/or visual alarm and/or a call to the nurses'station, which may be sent via the existing nurse call system in thehospital. The audio alarm may include playback of a prerecorded messagesuch as “Please remain in your bed.” Different messages may be playedback depending upon the signals received from the various sensing zones.For example, if a first signal is no longer received from first sensingzone 200, but a signal is received from second sensing zone 202 a (orthird sensing zone 202 b), controller 70 determines that the patient hasnot yet left the bed, but is about to leave the bed, and may play back amessage such as “Please remain in your bed. If you need assistanceplease use the nurse call button.” In this event, the nurses' stationmay or may not be called. However, if no signals are received fromeither the first or second sensing zones (or the third sensing zone) forthe predetermined time period, controller 70 determines that the patienthas left the bed, and may play back a message such as “Please return toyour bed. A nurse has been called.” In this event, the nurses' stationmay be called. Thus, not only may different messages be played backdepending upon the conditions, but calls to the nurses' station may bedependent upon the conditions sensed using multiple sensing zones.

Although the notification device 10 according to the third embodiment isonly described above as a patient movement notification device,conductive tracings similar to those in the first embodiment may beprovided on the upper surface of sensor pad 100 such that thenotification device may also function as an incontinence notificationdevice. Further, an absorbent chuck 150 may be combined with sensor pad100 in the same manner as discussed above with respect to the secondembodiment.

As mentioned above, another problem associated with patient movementnotification devices is that they may not operate accurately when usedon an air mattress, particularly for patients weighing between about 70and 150 pounds because the sensor pads do not effectively discriminatebetween a loss of pressure from above or below the sensor pad. Toaddress this problem, a fourth embodiment of a notification device 10includes a modified sensor pad 100 (FIG. 7) that includes a centralregion 250 and four depending legs 252 a-252 d. A first depending leg252 a extends from central region 250 in a first direction and a seconddepending leg 252 b extends from central region 250 in a seconddirection, which is opposite the first direction. A third depending leg252 c extends from central region 250 in a third direction, which issubstantially perpendicular to the first and second directions. A fourthdepending leg 252 d extends from central region 250 in a fourthdirection, which is opposite the third direction and substantiallyperpendicular to the first and second directions. By providing thedepending legs 252 a-252 d, the effective area of sensor pad 100 may beincreased without simply increasing the size of a conventionally-shapedsensor pad and thereby without also proportionally increasing thematerial cost of the sensor pad.

Although the notification device 10 according to the fourth embodimentis only described above as a patient movement notification device,conductive tracings similar to those in the first embodiment may beprovided on the upper surface of sensor pad 100 such that thenotification device 10 may also function as an incontinence notificationdevice. Further, an absorbent chuck 150 may be combined with sensor pad100 in the same manner as discussed above with respect to the secondembodiment. In addition, sensor pad 100 may include multiple sensingzones as described in the third embodiment.

For each of the embodiments described above, the sensor pad 100 isdisposable and would therefore be sold separately and configured to beremovably communicatively coupled to electronics module 15. Accordingly,for the four above embodiments, there are four additional embodimentsconstituting just the respective sensor pads, which may be used incombination with the absorbent chuck 150.

The electronics module 15 may be reusable or may be disposable asdescribed in U.S. Patent Application Publication No. US 2014/0221876 A1,the entire disclosure of which is incorporated herein by reference.

The benefit of making electronics module 15 disposable is that iteliminates the need for monitoring this portion of the notificationdevice as a capital asset. In addition, the electronics module may beconstructed to permanently shut itself down to become non-functional aspecified number of days after activation (i.e., 15 days fromactivation). In this way, the hospital can replace the sensors every 15days as recommended by only checking if the device has shut down or isabout to shut down rather than logging the dates of first use. In thisregard the electronics module may give an advance warning a few hours inadvance and then shuts down. Because the device may be designed to relaythe warning signal of patient movement to a nursing station, the devicemay further transmit the advance warning of shutdown to the nursingstation as well. It should be appreciated that the shutdown (or timeout) feature may be modified for non-disposable modules so that itprovides a warning that the 15-day period is over or almost over.

In the event that the electronics module is designed to be disposable,housing 20 (FIGS. 1 and 1A) may be designed so that it does not allowaccess to the battery 50 such that it cannot be replaced or removed.This reduces parts count and cost of the unit and provides aninexpensive mechanism for activating the device as described further.Housing 20 further may include a slot 22 positioned proximate one end 52of the battery 50 and a battery terminal 24 to which that end 52 ofbattery 50 connects as shown in partial cross section in FIG. 1A. Aplastic tab 30 is provided that extends from housing 20 through slot 22and between end 52 of battery 50 and terminal 24 so as to prevent theelectronics from receiving power until such time as a user pulls the tab30 from slot 22.

The pressure sensor of sensor pad 100 may have a conventionalconstruction or may have the construction shown in FIG. 8. Conventionalpressure sensors are constructed using three pieces of cardboard, two ofwhich are coated with conductive pads facing one another and a thirdpiece of cardboard having foam attached thereto is placed in between theother two pieces of cardboard. A wire is attached to each conductive padand then the sensor is sealed within a plastic pouch.

FIG. 8 shows an example of a pressure sensor 111 for sensor pad 100whereby the inside surfaces of a sheet 102 (such as a plastic sheet)have conductive ink printed thereon to form conductive contacts 104 and106. Wires 108 and 110 may then be secured to the conductive contactsand foam 112 may then be laid over one of the conductive contacts. Thesheet 102 may then be folded and sealed such that the conductivecontacts 104 and 106 face one another with foam 112 disposedtherebetween. Such a sensor 100 may be formed in many different sizesand shapes. The novel sensor thus has fewer parts and lower cost. Thesensor 100 shown in FIG. 8 is disclosed in commonly assigned U.S. PatentApplication Publication No. US 2014/0221876 A1, the entire disclosure ofwhich is incorporated herein by reference. A sensor pad having eitherthe conventional pressure sensor construction or the construction shownin FIG. 8, may be used in any of the above embodiments.

In addition to providing the sensor on a bed, chair or wheelchair,another version of the sensor may be placed on a toilet to notify acaretaker that the patient has attempted to get up from the toilet ontheir own. A sensor for such a toilet application may be constructedusing a flexible circuit that may be connected and adhered to a surfaceof the toilet that will contact the patient's skin. The device wouldthus sense the properties of human skin, not pressure. The unitactivates once the patient touches the flex circuit contacts.Alternatively, the toilet sensor may be configured to sense pressure andmay be placed between the toilet seat and the toilet bowl or on top ofthe toilet seat.

A low cost microcontroller may be used as controller 70 and may servemultiple purposes including: application logic, generating an alarmtone, coordinating the actions of other components, and switch sensing.One suitable microcontroller is the PIC24F04KA200. It is an inexpensiveentry level 16-bit controller in the PIC24 product catalogue fromMicrochip. This particular controller benefits from its low cost andsmall form factor. The microcontroller operates at low voltages,nominally 3.0V, but is capable of operating while the battery leveldrops over its operating life (2.8 V).

The controller 70 is responsible for coordinating the actions of thedevice. Specifically, if electronics module 15 is disposable, controller70 tracks the time that the unit is active (measured from initial powerup). This time is cumulative and is stored periodically in non-volatilememory 75 (preventing tampering). When a predetermined lifetime expires,controller 70 no longer provides its basic operating functions. Thisrequires the user to replace the unit.

The controller 70 does not have to actually record any sound data;however, it may control the state and operation of a voice recorder.Given user input (from the button 67 or the patient sensor), thecontroller will command the voice recorder to record or play back. Thevoice recorder is solely responsible for handling the audio details.

Playback of a recording may also be performed by the voice recorder. Thealarm tone that the unit may generate may be the controller'sresponsibility. This is done by simply toggling a pin that is connectedto the audio line. This appears as a square wave to an audio amplifier,which in turn generates a loud alarm. The controller controls thepower-up state of the audio amplifier. This is done to intelligentlyreduce power consumption during inactive periods. The controller turnsthe amplifier on only when required.

Lastly, the controller senses user input. The button 67B for recordingis tracked by the controller. More importantly the controller containsall of the hardware for sensing patient contact with an attached flexcircuit or patient sensor. The controller may be programmed through aPGM connector.

The outer surfaces of housing 20 and sensor pad 100 are preferablytreated with an antimicrobial substance. The surfaces of housing 20 andsensor pad 100 are coated with an antimicrobial treatment that may besprayed onto the surfaces using a solution and/or may be applied usingwipes soaked in such a solution. Suitable wipes and solutions aredisclosed in commonly assigned U.S. Pat. No. 8,491,922, the entiredisclosure of which is incorporated herein by reference.

FIGS. 9A and 9B show a diaper 300 having an integrated incontinencesensor pad 302 having a moisture-impermeable sheet 306 a with a firstcontiguous conductive tracing 304 a and a second contiguous conductivetracing 304 b both provided on an upper inner surface thereof forsensing moisture due to incontinence and generating a moisture detectionsignal when moisture spans the first and second conductive tracings 304a and 304 b. Diaper 300 further includes a moisture-impermeable sheet306 with an absorbent material 308 on an upper inner surface thereof.Moisture-impermeable sheet 306 has an aperture 310 for receiving sensorpad 302 such that first and second conductive tracings 304 a and 304 bon sensor pad 302 are exposed through or above aperture 310.Moisture-impermeable sheet 306 and absorbent material 308 may be made ofany conventional materials used in adult or baby diapers. The sensor pad302 may include a transmitter for wirelessly transmitting the moisturedetection signal to a notification device, which may be at a nurses'station.

Various aspects of the above embodiments may be integrated into a bed.For example, the patient movement notification device sensor pad 100 maybe integrated into a bed mattress. An example of such a bed 400 is shownin FIG. 10. In this case, the bed 400 may include an electronicinterface 402 to connect the integrated sensor pad 100 to electronicsmodule 15 via wired or wireless connection, and an absorbent chuck 150and incontinence sensor 406 may be provided on top of the mattress 404and may be connected to the electronic interface 402 included in the bed400 so that a common electronics module 15 or alarm interface may beused. Incontinence sensor 406 may include a moisture impermeable sheet408 with tracings 122 and 124 provided thereon.

The above description is considered that of the preferred embodimentsonly. Modifications of the invention will occur to those skilled in theart and to those who make or use the invention. Therefore, it isunderstood that the embodiments shown in the drawings and describedabove are merely for illustrative purposes and not intended to limit thescope of the invention, which is defined by any subsequently presentedclaims as interpreted according to the principles of patent law,including the doctrine of equivalents.

What is claimed is:
 1. A sensor pad for use in a notification device forproviding patient movement notification and incontinence notification,said sensor pad comprising: a sheet; a pressure sensor for sensingpressure applied by a patient and generating a pressure signal upon asensing pressure applied by the patient, the pressure sensor comprisingconductive ink printed on a first surface of the sheet to form first andsecond conductive contacts, and a foam provided over one of said firstand second conductive contacts; first and second contiguous conductivetracings provided on an upper outer surface of said sheet opposite thefirst surface on which said conductive ink is printed for sensingmoisture due to incontinence and generating a moisture detection signalwhen moisture spans said first and second conductive tracings, whereinsaid sheet is folded and sealed such that said first and secondconductive contacts are inside said sensor pad and face one another withsaid foam disposed therebetween to form said pressure sensor, and suchthat said first and second conductive tracings are located on the upperouter surface of said sensor pad.
 2. The sensor pad of claim 1 andfurther comprising: first and second wires each secured to a respectiveone of said first and second conductive contacts, wherein said first andsecond wires provide an electrical coupling to an electronics module ofthe notification device; and third and fourth wires each secured to arespective one of said first and second conductive tracings, whereinsaid third and fourth wires provide an electrical coupling to theelectronics module of the notification device.
 3. The sensor pad ofclaim 1, and further comprising: an absorbent chuck comprising amoisture-impermeable sheet with an absorbent material on an uppersurface thereof, wherein said moisture-impermeable sheet of said chuckhaving an aperture for receiving said sensor pad such that said firstand second conductive tracings on said sensor pad are exposed through orabove said aperture.
 4. The sensor pad of claim 1, wherein said sensorpad comprises: a central region; a first depending leg extending fromsaid central region in a first direction; a second depending legextending from said central region in a second direction, which isopposite the first direction; a third depending leg extending from saidcentral region in a third direction, which is substantiallyperpendicular to the first and second directions; and a fourth dependingleg extending from said central region in a fourth direction, which isopposite the third direction and substantially perpendicular to thefirst and second directions.
 5. A notification device for providingpatient movement notification and incontinence notification, the devicecomprising the sensor pad of claim 1 and an electronics modulecommunicatively coupled to said sensor pad for generating a notificationof patient movement in response to receipt of the pressure signal fromsaid sensor pad, and for generating a notification of incontinence inresponse to receipt of the moisture detection signal from said sensorpad.
 6. The notification device of claim 5, wherein the sensor padcomprises a first sensing zone and a second sensing zone, the firstsensing zone senses pressure applied by the patient to the first sensingzone and generates a first pressure signal upon a sensing pressureapplied by the patient to the first sensing zone, the second sensingzone senses pressure applied by the patient to the second sensing zoneand generates a second pressure signal upon a sensing pressure appliedby the patient to the second sensing zone, and wherein said electronicsmodule generates a notification of patient movement in response toreceipt or non-receipt of at least one of the first pressure signal andsecond pressure signal from said sensor pad.
 7. The notification deviceof claim 6, wherein said first sensing zone is located on the sensor padtowards the center of a bed where the patient is most likely to lie, andwherein said second sensing zone is located on the sensor pad towards aside of the bed where the patient may exit the bed.
 8. The notificationdevice of claim 7, wherein said electronics module enters a monitoringmode upon receipt of the first pressure signal, wherein receipt of thefirst pressure signal indicates that the patient is applying pressure tothe first sensing zone.
 9. The notification device of claim 8, wherein,when in the monitoring mode, said electronics module does not generate anotification of patient movement so long as the first pressure signal isreceived.
 10. The notification device of claim 8, wherein, when in themonitoring mode, said electronics module generates a notification ofpatient movement when the first pressure signal has not been receivedfor a predetermined time period.
 11. The notification device of claim 8,wherein, when in the monitoring mode, said electronics module generatesa notification of patient movement when the first pressure signal is nolonger being received but the second pressure signal is received therebyindicating that the patient has moved from the first sensing zone to thesecond sensing zone.
 12. The notification device of claim 7, whereinsaid sensor pad comprises a third sensing zone that senses pressureapplied by the patient to the third sensing zone and generates a thirdpressure signal upon a sensing pressure applied by the patient to thethird sensing zone, wherein said third sensing zone is located on thesensor pad on an end of said sensor pad opposite an end where saidsecond sensing zone is located so as to be positioned toward an oppositeside of the bed where the patient may exit the bed.
 13. The notificationdevice of claim 12, wherein said electronics module enters a monitoringmode upon receipt of the first pressure signal, wherein receipt of thefirst pressure signal indicates that the patient is applying pressure tothe first sensing zone.
 14. The notification device of claim 13,wherein, when in the monitoring mode, said electronics module generatesa notification of patient movement when the first pressure signal is nolonger being received, but either the second pressure signal or thethird pressure signal is received thereby indicating that the patienthas moved from the first sensing zone to either the second sensing zoneor the third sensing zone.
 15. The notification device of claim 6,wherein said sensor pad is integrated into a mattress of a bed.
 16. Thesensor pad of claim 1, wherein the sheet is made of a moistureimpervious material.